Questions tagged [polymorphism]
In computer science, polymorphism is a programming language feature that allows values of different data types to be handled using a uniform interface.
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Integration Test for Polymorphic data models that save data to MySQL
As noted by @TobySpeight in his answer to Polymorphic data models that save data to MySQL and restore data from MySQL the test code should also be reviewed. His ...
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Polymorphic data models that save data to MySQL and restore data from MySQL
This is a follow up question to Inserting and retrieving data MySql Database access in C++ using Boost::ASIO and Boost::MySQL. I have reduced the amount of code to be reviewed by presenting only one ...
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A static version of std::polymorphic
There sometimes is a desire to have access to the base class of a polymorphic object without wanting the overhead of dynamic allocation, see for example this question. For a more value-like way of ...
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Adapting a hierarchy of polymorphic classes to std::variant
The idea of the following is to adapt a hierarchy of polymorphic classes DerivedX to std::variant without modification to ...
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Maze game from book Design Patterns with smart pointers and polymorphism
The Design Patterns book chapter 3 about Creational Patterns starts with a maze game. They use the maze as an example throughout the chapter and instead of rooms they have also things like enchanted ...
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Runtime function overloading / dynamic dispatch for Python (2nd revision)
Second revision of the original post: Function overloading / dynamic dispatch for Python
TL;DR:
Improved version of this library[^1] based on previous reviews and criticism. It provides runtime ...
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A tree of polymorphic types (Crafting Interpreters Book)
I am following the book crafting interpreters by Robert Nystrom using C++. In the book we use an Expr base class to describe expressions in the language lox. ...
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Function overloading / dynamic dispatch for Python
UPDATE: Second revision on separate post. Runtime function overloading / dynamic dispatch for Python (2nd revision)
When I first started using Python I had a rough time dealing with some of it's ...
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polymorphic message container [closed]
Any comments/suggestions on this design? I just want to hold onto an ordered collection of messages. Each message can be one of several types.
I'm using some code analogous to this currently in a ...
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C++ compile time polymorphism example [closed]
I found an example using std::variant to provide compile time polymorphism as a possible optimisation to runtime polymorphism in 'Software Architecture Using C++', https://github.com/PacktPublishing/...
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Cache for mesh objects
I'm creating a cache system for an object (Mesh) that is expensive to create. A Mesh can be created using a small amount of ...
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Parametric visibility and order of tkinter labels
I'm writing software which allows a user to view data in a number of different formats, and they can switch between formats at any time. I'm wondering if there's a better way to do this than switching ...
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Logistics project that implements several shipping APIs
I have a Python logistic project that implements several shipping APIs using class inheritance. Each of those classes must do three things:
Fire requests to each endpoint with the proper parameters
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One-time dynamic, many-time *almost* static type dispatch
Annoyed at the tension between good software design principles that require well-defined delimitations between interface and implementations, and the requirements for critical code to run fast, which ...
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Gallery template class
I have created a template class Gallery which is intended to be used as a container for objects. I used a private member of type...
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Entity Framework - component shop using polymorphism and generic repository
I am creating a .NET Framework MVC EF application for PC components. I wanted to make full use of inheritance, polymorphism and generic repository pattern - but was wondering if my initial design ...
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Model animals using inheritance in Java, revised
Yesterday I posted my first solution to an interview problem here. I am now aware that I have many weak spots in Java and need to do extensive review before tackling any more interviews. Having said ...
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Inquiring possible alternatives to custom hierarchy-aware smart pointer
I have a medium sized project that uses a class hierarchy that essentially boils down to:
...
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C++: Event system for game engine
Since writing your own C++ game engine seems to be really popular these days (seriously just look at the amount of people presenting their WIPs on YouTube) I figured I'd try it myself.
My mental model ...
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Efficient vector-like polymorphic container which retains type information
This is my attempt of implementing an efficient, cache-friendly, vector for polymorphic objects.
From now on I will refer to "virtual functions" as functions which are dependent on an object'...
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Animal, Dog, and IDangerous - Using interfaces and inheritance with C#
I'm quite new to object-oriented C#. I wanted to test my knowledge by creating a Dog/Animal classes. I also tried to implement ...
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Banking system using polymorphism
I am asking this, because after studying I am confused that it is necessary to declare base class object, then declare derived class object and then store reference of derived class object in base ...
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POLYMORPHISM - Design a database connection and command
> Exercise 1: Design a database connection
To access a database, we need to open a connection to it first and close it once our job is done.
Connecting to a database depends on the type of the ...
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Dynamical system animation framework
Introduction
I am developing a dynamical system simulation/animation framework, which
provides three abstract base classes, DynamicalSystem, ...
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Supermarket Product Inventory Management with Polymorphic Product Types
The following method is used to add objects to a polymorphic ArrayList from a file.
It reads lines from the file, and based on a specific line which denotes the ...
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Manage Excel Styles with VBA OOP Approach (Follow up)
This is a follow up to this question
Code incorporates Mathieu's comments and it works. As some parts of the review left some code to my knowledge, I ask for another review to see if I implemented ...
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Manage Excel Styles with VBA OOP Approach
I want to manage the Excel Styles in a more flexible way with bulk actions and at the same time improve my newly acquired OOP concepts.
Objectives:
Load the current Styles list (name and type=builtin ...
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Implementation of tree with different node types and faux-polymorphism in C
I'm currently learning C by working on my first project.
It's a calculator with a parser that transforms input into an operator tree. These trees consist of nodes of different types: Operators (inner ...
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Polymorphic deleter for unique_ptr
There is a basic difference in the way C++ manages the deleter for std::unique_ptr and std::shared_ptr, mainly for allowing ...
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Builder pattern in C# supporting subclassing with nested classes [closed]
[Posted yesterday on Software Engineering, but was apparently "disappeared"...maybe better here]
Background: I am just starting to get my head around the idea of separating the domain model from the ...
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A polymorphic union in C++
Sometimes I use std::unique_ptr<BaseClass> when all I really want is polymorphism. For fun, I made this container that skips the heap allocation. The ...
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A C++17 std::function implementation
Some time ago I implemented dynamic_array and posted it on Code Review. It used std::function internally for type erasure. This ...
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Polymorphic DBConnector class exercise
GitHub
GitHub if it's easier
I'm in the process of doing a training course in C#. I've just gone over covering Polymorphic OOP / composition over inheritance etc...
The latest exercise I completed ...
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Polymorphism and inheritance in C99
In the following code I have created the something like the behavior of inheritance and methods in C99 (without vtable). The code compiles without any warnings even with ...
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Implementing different types of light sources in a Graphics project
Edit: I got asked a lot why I need to have the LightSource base class or why do I keep one vector of all the light sources, so here's my explanation:
In many ...
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Polymorphic implementation for == with CRTP
I'm trying to implement equality for all types that share same base.
Consider std::vector<unique_ptr<Shape>> and that we want to check if a certain ...
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Managing different types of morphism and their compositions
Here's some code I wrote to manage the different types of morphism and their compositions in C++17.
Let me know if you had any suggestions for substantial simplifications or improvements, or if I ...
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Making TypeNameHandling in json.net more convenient
Handling abstract types in json.net can be sometimes challenging because it requires a very long and complex syntax like:
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Creating an array of distinct objects with an identical method that can be evaluated (mapped) at compile-time (constexpr)
In a ray tracing project that I'm trying to make compile-time (constexpr) for fun and challenge, I've run into a bit of an issue: I have an object (intersection) that needs to refer to one of a group ...
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Curiously Recurring Template Pattern (CRTP) implementation
I'm implementing Curiously Recurring Template Pattern(CRTP) in Java as follows.
The Interface:
...
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Area calculator for shapes as an OOP interview test
A while ago a tricky C++ interview question came across to me, and ever since I could not tell what I did wrong.
Create a base class named “Shape” with a method to return the area of the shape. ...
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Function overloading in Python
Motivation
As an exercise, I wanted to try implementing function overloading in Python 3, i.e. to implement a way of defining multiple functions with the same name and then calling the appropriate ...
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Simple trie class in C++
I would be very grateful to get some thoughts on this toy-implementation of a trie that I wrote to practice my C++.
Some questions I have:
Is my create member ...
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Drawing various types of shapes [closed]
I did the following Excercise:
simulate single inheritance in C. Let each "base
class" contain a pointer to an array of pointers to functions (to simulate
virtual functions as freestanding ...
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CUDA/C++ Host/Device Polymorphic Class Implementation
I have an abstract class which acts as in interface for a variety of physical models providing Electric/Magnetic Fields as the result of a number of phenomena. I'm wondering if how I've done it is a ...
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Classes for shapes and development [closed]
Task
You should create an abstract Shape class that contains the stuff that would be similar across all shapes, and change Line and Rectangle so that they extend Shape. Then, in the DrawingModel ...
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Rust idiomatic way of polymorphic struct
I've implemented a simple polymorphic structure, which looks a bit ugly and I'm afraid I am missing an idiomatic way of doing it.
To describe briefly what I'm trying to achieve here: I would like to ...
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Polymorphism with overrides and base calls simulating an employee
I've studied and worked a lot on the subject for a month or two to get closer to the concept in a cleaner way, i.e. no virtual tables and no bunch of functions with prefixes etc. and most importantly ...
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Simple implementation of signals and slots mechanism using templates
I tried to implement a simple signal&slots mechanism for some DSP software that runs on embedded Linux. I would like if somebody can review this code and give me some guidelines. Any review and ...
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Vehicle, Components and Car relationship [closed]
I am writing Vehicle - Components - Car relationship.
I have to separate cars that use the diesel, petrol and electric engines because each of them produce their own results (but methods of each are ...
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